Contact spring assembly

ABSTRACT

A female power contact assembly is provided for both parallel and tandem blades or any combination thereof. The assembly comprises two contact arms constituting a U-shaped contact for tandem blades, and a single contact arm riveted to one side of the U-shaped contact and constituting a second contact therewith for parallel blades. The single contact arm is part of a combination of a contact arm and binding plate.

United States Patent Gartland, Jr. et al. 145 Jul 11, 1972 1541 CONTACT SPRING ASSEMBLY 2,214,065 9/1940 Pennock et a1 ..339/31 M 72 Inventors: Albert J. Gartland, .11., Trumbull; Michael {2352}: :33; "533%? J. DAmato New Haven both of Conn. my

1,602,370 10/1926 Avery ..339/33 73 Assignee: Harvey nubbeu Incorporated, Bridgepon, 1,146,938 7/1915 Hubbell ..339/191 x Conn. Primary Examiner.loseph H. McGlynn [22] Filed: 1970 Assistant Examiner-Robert A. l-lafer [21 1 App. No; 85,471 Attorney-Wooster, Davis & Cifelli [57] ABSTRACT 52 US. Cl. ..339 33, 339 259 R, 339 262 R i511 1111. Cl ..H0lr 27/00 A female Power assembly Pmv'ded Parallel [58] Field of Search ..339/14 262 191 192 31 andem blades any cmbinafin time The assembly 339/32 33 154 63 comprises two contact arms constituting a U-shaped contact for tandem blades, and a single contact arm riveted to one side of the U-shaped contact and constituting a second contact [56] References cued therewith for parallel blades. The single contact arm is part of NI D STATES P T S a combination of a contact arm and binding plate. 994,516 6/191 1 Hubbell ..339/191 A 10 Claims, 7 Drawing Figures CONTACT srnmo ASSEMBLY BACKGROUND OF THE INVENTION The present invention relates to an improved female contact spring assembly for straight bladed male devices.

In wiring devices of the straight blade type, it is essential that female power contacts create high bearing loads on male blades inserted therein in order to provide adequate contact pressure and blade retention. Many problems are involved with the creation and maintenance of the high bearing loads. The most serious problems are those brought about by the necessity for the female contacts to be capable of accepting not only a wide range of blades of different thickness but also both tandem and parallel blades. Various contacts of this type are known, and are particularly advantageous from manufacturing viewpoints. However, it has been found that the blade retention and bearing loads of such contacts is inadequate.

SUMMARY OF THE INVENTION With the foregoing in mind, it is the object of the invention to provide an improved female power contact assembly for both parallel and tandem blades or any combination thereof and which, moreover, comprises novel means to increase the bearing loads on and retention of male blades.

Such an improved female power contact assembly according to the invention comprises first and second contact arms constituting a first- U-shaped contact for tandem blades and a third comparatively wide contact arm connected to one side of the first and second contact arms and constituting a second contact therewithfor parallel blades. Lug members are provided to restrict outward deflection of the first and second contact arms relative to each other such as to increase blade retention and high bearing loads on the tandem blades. Such loads on the parallel blades are provided by means of the wide third contact arm while blade retention is increased by means of a nib member constantly biasing the third arm against the first and second arms.

BRIEF DESCRIPTION OF THE DRAWINGS The manner in which these and other objects of the invention are achieved will be best understood by reference to the following description, the appended claims, and the figures of the attached drawings wherein:

FIG. 1 is a composite perspective view of an electrical connector embodying the power contact assembly of the invention;

FIG. 2 is a top view of the female electrical receptacle incorporated in the connector of FIG. 1, and illustrating the contact assembly in electrical connection with tandem blades;

FIG. 3 is a perspective view illustrating the female power contact assembly according to the invention;

FIG. 4 is a cross-sectional view taken on line 4-4 of FIG. 3;

FIG. 5 is a cross-sectional view taken on line 5-5 of FIG. 4;

FIG. 6 is a cross-sectional view taken on line 6-6 of FIG. 5; and

FIG. 7 is a view similar to FIG. 2 but illustrating the contact assembly in electrical connection with parallel blades.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings in which like reference numerals index like parts and with attention initially directed to FIG. I, there is illustrated, for illustration purposes only, an electrical connector, generally indexed by the reference numeral 10. The connector 10 includes a male device 12 having male electrical line blades 14, and a grounding blade 16, a female device 18 having female electrical contacts 20, and a grounding contact 22, and an insulator cap 24 enclosing the female contacts. Clamping means, generally indexed by reference numeral 26, are provided to retain the electrical wire or cable ends (not shown) connected, in conventional manner, to the blades, 14, 16, and contacts, 20, 22, within the male and female devices. l2, 18. The line blades 14 are of the straight-blade parallel type and are received in the female contacts 20 embodied according to the invention. The grounding blade 16 is of the U-shape type and is received in the usual spring grounding contact 22.

The contacts 20, as clearly shown in FIGS. 3-6, are seen to comprise a first, generally U-shaped contact, generally indexed with reference numeral 28. The first contact 28 includes first and second integral contact arms, 30, 32, having a common base 34. The upper contact ends, 36, 38, are outwardly bent so as to facilitate insertion of the male blades. Formed integral with the base 34, is a connecting bridge, generally indexed with reference numeral 40, FIG. 6. The bridge comprises an upright or vertical portion 42 provided with a pair of projecting lugs, 44, 46, abutting the arms, 30, 32, at the outer sides thereof. The lugs are provided to restrict outward deflection of the arms, 30, 32, relative to each other upon insertion of male blades therebetween. Such insertion and restriction is illustrated in FIG. 2. The blades used are of the straight-blade tandem type and are indexed by the reference numerals, 48, 50. Restriction of the deflection of the arms is at a point between the application of the load, i.e., the blades, 48, 50, and the usual fixed point or that point where the contact arms join each other at the center of base 34. In this manner, provision is made for the insertion of a long male blade while the efiective length of the arms, 30, 32, is made comparatively shorter than arms of conventional contacts having no such deflection restricting lugs. Moreover, the provision of the lugs and the relatively short arms, 30, 32, effect very high bearing loads at the point of contact with the male blade. I

The contacts 20 further include an integral combination contact arm and binding plate, generally indexed by reference numeral 52. The contact arm 54 is comparatively wide and is seen to be fixedly connected to upstanding portion 42 of the connecting bridge 40 at one side of the arms, 30, 32. In this instance, such connection is accomplished by means of a rivet 56 extending through rivet holes provided in both the upstanding portion 42 and the bridge 40. The rivet head, 56a, preferably, is positioned inwards of the bridge 40. As shown in FIG. 6, the upper contact end 58 of the arm 54 firmly abuts the upper contact ends of the arms, 30, 32, at one side thereof. At its lower end, the arm 54 is connected with the binding plate 60 via a transverse connecting portion 62. At its upper side, connecting portion 62 contacts a comparatively small, generally semi-circular nib 64 which is formed at the under surface of base 34 and biases the contact end of arm 54 against the sides of contact arms, 30, 32. The provision of the nib 64 ensures a tight contact and retention of a male parallel blade inserted between the arm 54 and the sides of arms, 30, 32. Such contact and retention of a parallel blade across the respective points of contact is achieved regardless of varia tions in the relative locations of the rivet due to normal manufacturing tolerances. Moreover, the nib provides large deflections of the wide contact arm 54 which results in high bearing loads on an inserted parallel blade. At its outermost end, the arm 54 is bent outwardly away from the arms, 30, 32, so as to facilitate insertion of the parallel male blade. Such insertion and retention of male blades between the arm 54 and the sides of arms, 30, 32, is illustrated in FIG. 7. The blades, in this instance, are the parallel blades 14. The lowermost end of binding plate 60 is connected in any suitable manner in the female device 18 and includes a binding screw 66 for the connection of an electrical wire end (not shown) to the plate 60.

Either a tandem or parallel male bladed male connector or a male connector having any desired combination of such blades may be selectively connected to the female connector device 18 by having the blades inserted through a pair of usual T-slots 68 formed in cap 24, and such male blades will be automatically and properly accommodated in the female contacts 20. If the male connector device is a grounding one, as is the illustrated connector device 12, the male grounding blade 16 is inserted through slot 70 formed in the cap 24 into engagement with the female grounding contact.

It is believed that the many advantages of this invention will now be apparent to those skilled in the art. It will also be apparent that a number of variations and modifications may be made without departing from its spirit and scope. Accordingly, the foregoing description is to be construed as illustrative only, rather than limiting.

What is claimed is:

1. A female contact spring assembly for use with straightbladed male devices of either the tandem or parallel blade type comprising: first and second contact arms interconnected by a common base to constitute a U-shaped female contact for receiving a tandem male blade; a third contact arm connected to said common base and abutting one side of each of said first and second contact arms and cooperating therewith for receiving a parallel male blade; and means integral with said contact spring assembly arranged to be engaged by said first and second contact arms to restrict their deflection upon their receiving a tandem male blade therebetween.

2. A female contact spring assembly for use with straightbladed male devices of either the tandem or parallel blade type comprising: a first contact comprising integral first and second contact arms interconnected by a common base and constituting a U-shaped female contact for receiving a tandem male blade; and a second contact comprising a third contact arm connected to said U-shaped contact and abutting one side of each of said first and second contact arms and cooperating therewith for receiving a parallel male blade; said common base includes an upright portion directed upwardly therefrom which, in turn, has portions projecting laterally therefrom to positions in which said projecting portions flank said first and second contact arms and are arranged to be engaged by said first and second contact arms to restrict the deflection of said first and second contact arms upon inserting a tandem male blade between said first and second contact arms.

3. The assembly as defined in claim 2 wherein said third contact arm is fixed to said upright portion.

4. The assembly as defined in claim 3, wherein said third contact arm is riveted to said upright portion.

5. The assembly as defined in claim 2, wherein said third contact arm includes a terminal portion having a binding screw attached thereto.

6. An electrical female connector device comprising a hous ing of electrical insulating material; a pair of female contact assemblies as defined in claim 2 mounted within said housing; and a pair of T-slots formed in said housing and oriented relative to said assemblies to permit selective insertion of either parallel or tandem male blades through said slots into said housing into proper electrical engagement with said female contact assemblies.

7. A female contact spring assembly for use with straightbladed male devices comprising: first and second contact arms interconnected by a common base to constitute a U-shaped female contact for receiving a straight male blade in one direction; a third contact arm connected to said common base andabutting one side of each of said first and second contact arms and cooperating therewith for receiving a straight male blade in one direction; and means integral with said contact spring axially arranged to be engaged by said first and second contact arms to restrict their deflection upon their receiving a male blade therebetween.

8. An electrical female connector device comprising a housing of electrical insulating material; a pair of female contact assemblies as defined in claim 7 mounted within said housing and arranged to receive either a pair of tandem male blades or a pair of parallel contact blades or a pair of any combination of such blades; and a pair of slots formed in said housing; said slots configured so as to selectively admit a pair of either tandem or parallel male blades or a combination of them; and said slots being oriented relative to said assemblies to permit selective insertion of said pair of male blades through said slots into said housing into proper electrical engagement with said assemblies. I

9. A female contact spring assembly for use with straightbladed male devices of either the tandem or parallel blade type comprising: a first contact comprising integral first and second contact arms interconnected by a common base and constituting a U-shaped female contact for receiving a tandem male blade; and a second contact comprising a third contact arm connected to said U-shaped contact and abutting one side of each of said first and second contact arms and cooperating therewith for receiving a parallel male blade; said third contact arm includes a bent-in portion extending parallel with said common base; and a nib is provided on said common base for engaging said bent-in portion to bias said third contact arm against said first and second contact arms to restrict deflection of said third contact arm relative to said first and second contact arms upon insertion of a male parallel blade between the sides of said first and second contact arms and said third contact arm.

10. A female contact spring assembly for use with straightbladed male devices of either the tandem or parallel blade type comprising: a first contact comprising integral first and second contact arms interconnected by a common base and constituting a U-shaped female contact for receiving a tandem male blade, said common base includes an upright portion from which lugs project laterally; and a second contact comprising a third contact arm connected to said upright portion of said common base and abutting one side of each of said first and second contact arms and cooperating therewith for receiving a parallel male blade; said lugs projecting from said upright portion are arranged to be engaged by said first and second contact arms to restrict their deflection upon insertion of a male tandem blade therebetween; said third contact arm includes a bent-in portion extending parallel with said common base; and a nib formed on said common base and arranged to engage said bent-in portion and bias said third contact arm against the side of said first and second contact arms to restrict deflection of said third contact arm relative to said first and second contact arm upon insertion of a male parallel blade between the sides of said first and second contact arms and said third arm.

222 3 UNITED STATES PATENT OFFICE CERTIFIfiATE 0F CQRRECTIUN latent No. I Dated y 97 Albert J. Gartland, Jr. and Michael J. D 'Amato Inventofls) It is certified that error appears in the above-identified patent and that said Letters Patent: are hereby corrected as shown below:

f I n Column 1, line 28, om1t-"-"' after "firscfl, I See specification as filed, page 2, line l l. Column 3 (Claim 3) line 35 insert.a comma.- after "2".

See or ginal-claims as filed, and amended Dec. 2, 1971 Column 4, (Claim 7) line 2, delete "axially" and insert therefl assembly-.- I I D See Examiner's amendment, (original claim 9) mailed Januar 24, 1972.

' Signed and sealed this "2nd day of January 1973.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

1. A female contact spring assembly for use with straight-bladed male devices of either the tandem or parallel blade type comprising: first and second contact arms interconnected by a common base to constitute a U-shaped female contact for receiving a tandem male blade; a third contact arm connected to said common base and abutting one side of each of said first and second contact arms and cooperating therewith for receiving a parallel male blade; and means integral with said contact spring assembly arranged to be engaged by said first and second contact arms to restrict their deflection upon their receiving a tandem male blade therebetween.
 2. A female contact spring assembly for use with straight-bladed male devices of either the tandem or parallel blade type comprising: a first contact comprising integral first and second contact arms interconnected by a common base and constituting a U-shaped female contact for receiving a tandem male blade; and a second contact comprising a third contact arm connected to said U-shaped contact and abutting one side of each of said first and second contact arms and cooperating therewith for receiving a parallel male blade; said common base includes an upright portion directed upwardly therefrom which, in turn, has portions projecting laterally therefrom to positions in which said projecting portions flank said first and second contact arms and are arranged to be engaged by said first and second contact arms to restrict the deflection of said first and second contact arms upon inserting a tandem male blade between said first and second contact arms.
 3. The assembly as defined in claim 2 wherein said third contact arm is fixed to said upright portion.
 4. The assembly as defined in claim 3, wherein said third contact arm is riveted to said upright portion.
 5. The assembly as defined in claim 2, wherein said third contact arm includes a terminal portion having a binding screw attached thereto.
 6. An electrical female connector device comprising a housing of electrical insulating material; a pair of female contact assemblies as defined in claim 2 mounted within said housing; and a pair of T-slots formed in said housing and oriented relative to said assemblies to permit selective insertion of either parallel or tandem male blades through said slots into saId housing into proper electrical engagement with said female contact assemblies.
 7. A female contact spring assembly for use with straight-bladed male devices comprising: first and second contact arms interconnected by a common base to constitute a U-shaped female contact for receiving a straight male blade in one direction; a third contact arm connected to said common base and abutting one side of each of said first and second contact arms and cooperating therewith for receiving a straight male blade in one direction; and means integral with said contact spring axially arranged to be engaged by said first and second contact arms to restrict their deflection upon their receiving a male blade therebetween.
 8. An electrical female connector device comprising a housing of electrical insulating material; a pair of female contact assemblies as defined in claim 7 mounted within said housing and arranged to receive either a pair of tandem male blades or a pair of parallel contact blades or a pair of any combination of such blades; and a pair of slots formed in said housing; said slots configured so as to selectively admit a pair of either tandem or parallel male blades or a combination of them; and said slots being oriented relative to said assemblies to permit selective insertion of said pair of male blades through said slots into said housing into proper electrical engagement with said assemblies.
 9. A female contact spring assembly for use with straight-bladed male devices of either the tandem or parallel blade type comprising: a first contact comprising integral first and second contact arms interconnected by a common base and constituting a U-shaped female contact for receiving a tandem male blade; and a second contact comprising a third contact arm connected to said U-shaped contact and abutting one side of each of said first and second contact arms and cooperating therewith for receiving a parallel male blade; said third contact arm includes a bent-in portion extending parallel with said common base; and a nib is provided on said common base for engaging said bent-in portion to bias said third contact arm against said first and second contact arms to restrict deflection of said third contact arm relative to said first and second contact arms upon insertion of a male parallel blade between the sides of said first and second contact arms and said third contact arm.
 10. A female contact spring assembly for use with straight-bladed male devices of either the tandem or parallel blade type comprising: a first contact comprising integral first and second contact arms interconnected by a common base and constituting a U-shaped female contact for receiving a tandem male blade, said common base includes an upright portion from which lugs project laterally; and a second contact comprising a third contact arm connected to said upright portion of said common base and abutting one side of each of said first and second contact arms and cooperating therewith for receiving a parallel male blade; said lugs projecting from said upright portion are arranged to be engaged by said first and second contact arms to restrict their deflection upon insertion of a male tandem blade therebetween; said third contact arm includes a bent-in portion extending parallel with said common base; and a nib formed on said common base and arranged to engage said bent-in portion and bias said third contact arm against the side of said first and second contact arms to restrict deflection of said third contact arm relative to said first and second contact arm upon insertion of a male parallel blade between the sides of said first and second contact arms and said third arm. 